A method for reducing fouling on the surfaces of equipment used in the high temperature treatment of petroleum feedstocks comprising treating the petroleum feedstock with at least 5 parts per million of a compound having the formula: ##STR3## wherein Q is Z, or R with the proviso that two occurances of Q are Z, R is hydrogen, or a straight or branched alkyl group having from 1 to 7 and most preferably from 1 to 4 carbon atoms, and only one or two occurances of R may be alkyl;
Z is represented by the formula: ##STR4## wherein R.sub.2 and R.sub.3 are the same as R and only one or two occurances of each of R.sub.2 or R.sub.3 may be alkyl, and "n" is a whole number of from 1 to 9, preferably 1 to 5, and most preferably, "n" is 1 to 3. In an especially preferred embodiment of the invention, "n" is 1, and R, R.sub.2 and R.sub.3 represent hydrogen. PA1 Z is represented by the formula: ##STR6## wherein R.sub.2 and R.sub.3 are the same as R and only one or two occurances of each of R.sub.2 or R.sub.3 may be alkyl, and "n" is a whole number of from 1 to 9, preferably 1 to 5, and most preferably, "n" is 1 to 3. In an especially preferred embodiment of the invention, "n" is 1, and R, R.sub.2 and R.sub.3 represent hydrogen.